1. Field
The present invention generally relates to an ultrasound system, and more particularly to an ultrasound system and method for controlling steering angles of scan lines set at each transducer element in a curved linear probe.
2. Background
An ultrasound system has become an important and popular diagnostic tool since it has a wide range of applications. Specifically, due to its non-invasive and non-destructive nature, the ultrasound system has been extensively used in the medical profession. Modern high-performance ultrasound systems and techniques are commonly used to produce two or three-dimensional images of internal features of an object (e.g., human organs).
The ultrasound system generally uses a probe containing a wide bandwidth transducer to transmit and receive ultrasound signals. The ultrasound system forms images of human internal tissues by electrically exciting an acoustic transducer element or an array of acoustic transducer elements to generate ultrasound signals that travel into the body. The ultrasound signals produce ultrasound echo signals since they are reflected from body tissues, which appear as discontinuities to the propagating ultrasound signals. Various ultrasound echo signals return to the transducer element and are converted into electrical signals, which are amplified and processed to produce ultrasound data for an image of the tissues.
Recently, a curved linear probe containing a curved linear transducer array has been used to obtain an ultrasound image of a wide viewing angle. The curved linear probe transmits the ultrasound signals along scan lines, which are set in a normal direction of a probe face representing a surface of the curved linear probe for transmitting and receiving the ultrasound signals. The curved linear probe transmits the ultrasound signals in a radial shape, thereby obtaining a wider ultrasound image than a length of the curved linear probe. FIG. 1 is a schematic diagram illustrating a geometrical structure of scan lines set at each transducer element in the curved linear probe. As illustrated in FIG. 1, if each scan line is extended backward from the transducer elements 12, then all the scan lines pass through a specific point 30 (hereinafter referred to as a “common point”). If the common point is moved as shown in FIG. 2, then a steering angle of the scan line is defined according to a position of the moved common point. Then, the scan lines 22 are set according to the defined steering angle so that an ultrasound image having a wider viewing angle can be obtained.
However, when the common point 30 varies, the conventional ultrasound system must calculate the steering angle of each scan line set at each transducer element. Therefore, there is a problem in that an extensive amount of time is consumed due to the need to perform complex steering angle calculations.